The present invention relates to a control valve for heating a pressure medium and maintaining its temperature constant in a hydraulic device.
Control valves of the above-mentioned general type are known in the art. In a known control valve, a thermosensor is arranged in a pilot valve. Upon exceeding of a fixed operational temperature the thermosensor provides for a bypass via an additional control element for a pressure medium flowing through the control valve. Thereby the control parts are adjusted so that the desired temperature is again attained. Such a valve provides for a sufficient maintenance of the pressure medium temperature. However, it is relatively expensive and not optimal in its operational safety.